Research efforts of the Poly-Orth International demonstrated feasibility of the novel ?Residuum-Integration Prosthetic Technology to be used in direct skeletal attachment of limb prosthetics. The technology includes a ?Skin and Bone Integrated Pylon? (SBIP), which connects the residuum with external limb prosthesis and can be especially beneficial for patients who can not use traditional socket attachment of the prostheses. As histopathology analysis after the study with small animals has demonstrated, the SBIP is integrated not only with the residual bone, but also with the residuum's skin minimizing the risk of infection and secondary trauma. The investigators developed an optimal porous titanium matrix and design of the Skin and Bone Integrated Pylon to maximize the ingrowth of bone and skin cells of the residuum to the SBIP without compromising strength of the implanted device. The technological study on the process of manufacturing of the composite porous structure enforced with a permeable internal frame. Parameters of the SBIP's specification are protected by the US Patent #8257435. During the proposed translational pre-clinical study the animal trials will be conducted according to the FDA requirements to ensure smooth translation to the trials in humans. It will include large animals and the implantation period up to 22 months.